diff --git a/pcdet/models/backbones_3d/vfe/image_vfe_modules/ffn/ddn_loss/__init__.py b/pcdet/models/backbones_3d/vfe/image_vfe_modules/ffn/ddn_loss/__init__.py
new file mode 100644
index 0000000..0ff8b2b
--- /dev/null
+++ b/pcdet/models/backbones_3d/vfe/image_vfe_modules/ffn/ddn_loss/__init__.py
@@ -0,0 +1,5 @@
+from .ddn_loss import DDNLoss
+
+__all__ = {
+    "DDNLoss": DDNLoss
+}